.button-container {
    /*width: 100px;*/
    /*height: 20px;*/

    position: fixed;
    top: 200px;
    left: 900px;
    width: 350px;
    height: 300px;
    background-color: rgba(57, 208, 243, 0.5);
    display: none; /* 默认隐藏 */
}

/*.button-container {*/
/*    width: 100%;*/
/*    height: 100%*/
/*}*/